Prefabricated wall



PREF'ABRICATED WALL 6 Sheets-Sheet 2 Filed July 14, 1954 Inventors: ToH I EOIJARO sml'fli Roam-r srunnonmz cnnmmnf mu Rnun hRcmBu-D ROCOCK J. E. SMITH ET AL Nov. 10, 1959 PREFABRICATED WALL 6 Sheets-Sheet 3 Filed July 14, 1954 United States PatentO PREFABRICATED WALL John Edward Smith and Robert Studholme Charlton, Leicester, and Ralph Archibald Grocock, Wigston =Fields, England Application July 14, 1954, Serial No. 443,334

Claims priority, application Great Britain January 12, 1954 '6 Claims. (Cl. 72--'16) This invention relates to buildings and like structures which are principally, or in part, prefabricated and adapted to be assembled, in situ, from precast concrete or similar components.

Although principally intended for application to newtraditional private dwelling houses, the invention is by no means limited in this respect as it may also be embodied in flats, schools, storehouses, factories, farm buildings, and any appropriate analogous structures of a permanent character.

The primary object of the invention is to provide an improved economical and eflicient system of building walls, more especially outer walls, of buildings designed to make use of readily available materials and minimise the use of materials such as bricks which are periodically in short supply, such walls being so constructed that the essential features thereof blend with traditional construction.

Another object is to provide a building at least the main shell of which is prefabricated of relatively light precast components designated both to facilitate and expedite light mechanical handling during assembly on the site whereby a substantial reduction in manual labour is effected.

A still further aim is the provision of the individual reinforced concrete or like columns, cladding and panelling slabs or blocks, plinth blocks, combined lintel and troughing course blocks, and other precast components of improved forms suitable for use in the aforementioned system of building, as will be hereinafter described.

The invention provides a prefabricated wall, comprising, in combination, a base composed of a course of precast plinth blocks having reentrant portions in their respective top surfaces so as to form recesses spaced from each other horizontally at predetermined intervals; a plurality of precast upright columns of reinforced concrete, each of said columns being inserted with its lower end in one of said recesses whereby said columns are spaced at said intervals, said columns having reinforcing bars extending longitudinally thereof and projecting with a portion thereof beyond the top of the respective column, said columns further having a number of longitudinally extending faces of which at least one is an outside face and at least one other face is a lateral face having a first edge defined by the intersection of said lateral face with said outside face, and a second edge remote therefrom said lateral face having an outwardly diverging dovetail portion adjacent to at least one of said edges; and outer leaf comprising at least one course of external cladding slabs each having an outer and inner face and lateral end edges facing in the longitudinal direction of said course, the end edges of any one slab and of a neighboring slab, respectively, extending parallel with and adjacent to each other in the plane of said outer faces thereof and being aligned with each other, while .said inner faces of said slabs are provided with reentrant dovetail recesses extending parallel with said lateral end .edges and being spaced from each other, each of said respectively, of said spaced reentrant dovetail recesses with the corresponding diverging dovetail portions of said columns; and a wall top including a course of precast lintel units having an upwardly open channel portion and a flat bottom portion with recesses therein forming openings spaced from each other at said predetermined intervals, said lintel units being placed with said flat bottom portions on top of said columns with said projecting portions of said reinforcing bars thereof extending through said openings, said lintel units being permanently connected with said column-s by concrete filled in situ into said channel portions and into said openings.

For a fuller understanding of the nature and objects of the invention reference should be had to the following detailed description taken in connection with the accompanying drawings exemplifying the invention, in which:

Figure 1 is an elevational view of a portion of the characteristic external wall construction,

Figure 2 is a vertical sectional view through the said wall construction,

Figure 3 is a fragmentary perspective View, partly in section, illustrating the preferred construction of the improved wall in which there are applied to a single series of precast upright columns both external slab cladding and also internal block panelling constituting an inner leaf,

Figure 4 is a similar view of a modification in which the inner leaf consists simply of boarding,

Figure 5 is a layout, in plan, of the plinth blocks relating to one of a pair of semi-detached houses,

Figure 6 is a plan view of one of the common, i.e. normal, plinth blocks,

Figure 7 is a cross-sectional view of the same taken on the line VIIVII of Figure 6,

Figure 8 is a plan of a plinth quoin, i.e. corner, block,

Figure 9 is a plan of a threshold plinth block,

Figure 10 is a front elevational view of the said threshold block,

Figure 11 is a cross-section taken on the line XIXI of Figure 9,

Figure 12 is a perspective view from the front, and showing the left-hand side, of a common column,

Figure 13 is a further perspective view of the common column from the rear and right-hand side thereof,

Figures 14, 15 and 16 are three horizontal cross-sectional views taken respectively on the lines XIVXIV, XV-XV and XVI-XVI of Figure 12,

Figures 17 and 18 are two views similar to Figures 12 and 13 respectively of a window jamb column,

Figures '19, 20, 21, 22 and 23 are horizontal crosssectional views taken on the lines XIX-XIX, XX-XX, XXIXXI, XXII-XXII, XXIIIXXIII of Figure 17.

Figure 24 is a perspective view from the front and left-hand side of a window mullion column,

Figure 25 is another perspective view from the rear and the right-hand side of the last mentioned column,

Figures 26, 27, 28, 29 and 30 are five horizontal crosssectional views taken on the lines XXVIXXVI, XXVIIXXVH, XXVIIIXXVIII, X)GX)Q(IX, and XXXXXX of Figure 24,

Figures 31 and 32 are front perspective views of a door jamb column as seen from the left and right hand sides respectively,

Figures 33, 34 and 35 are horizontal cross-sectional views taken on the lines XXXIII-XXXlII, XXXIV- XXXIV and XXXV-XXXV of Figure 31,

Figures 36 and 37 are perspective views depicting the left and right-hand sides of a corner column,

Figures 38 and 39 are two cross-sectional views of 3 the same taken on the lines X)Q(VIII-XXXVIII and XXXIXXXXlX of Figure 36,

Figures 40 to 43 are plan views of the various forms of external cladding slabs employed,

Figure 44 is a cross-sectional view of any one ofthe said cladding slabs,

Figure 45 is a detail plan view showing external cladding slabs and internal panelling blocks and the manner in which these are interlocked with common and window columns,

Figure 45a is a detail plan view depicting the manner in which cladding slabs can be pushed straight back into position beyond the widest outer portion of a dovetail formation,

Figure 46 is a view somewhat similar to Figure 45 illustrating the interlocking of such slabs and blocks with door and corner columns,

Figure 47 is a diagrammatic layout, in plan, of the lintel-troughing course, relating to one house only of a semi-detached pair,

Figure 48 is a plan view of a normal lintel-troughing block,

Figure 49 is a cross-sectional view of the said block taken on the line LVIlI-LVIII of Figure 48,

Figure 50 is a general perspective view of the same lintel troughing block,

Figure 51 is a plan view of a quoin lintel-troughing block,

The wall W depicted in Figure 1 comprises, in combination, a plinth course indicated generally at 3, .precast upright reinforced concrete columns such as 4, 5, 6, 7, and 8 seating in the plinth course, precast external cladding slabs such as 10, 11, 12 and 13 (Figures 40-43) which are laid horizontally, interfitted with the columns and cemented in position in such a way as to be tied by mating dovetail formations respectively on and in the said columns and slabs, internal panelling-blocks or panel fillers such as 14, which are also suitably laid and similarly interfitted with the columns, and a lintel troughing course 18 combined with bonding means at the heads of the columns.

The said plinth course is laid, as illustrated in Figure 2, on an 11" thick cavity wall 19 of traditional brickwork which is built on suitable foundations 20 and is filled with concrete at 21. Between the top of the filled brick-built cavity wall 19 and the undersides of the individual plinth blocks presently to be described there is interposed a bituminous felt damp course 22. From Figure 5 it will be seen that the plinth course 3 in respect of a semi-detached house is composed of a plurality of common, i.e. basic or normal, plinth blocks 23, quoin blocks 24, a front porch threshold 25, a single plinth block 26 which is longer than the common blocks 23 and is inserted at the bottom of the rear wall of the house to balance the threshold 25 at the front of the latter, and a kitchen door threshold 27 incorporated into the left-hand side wall. The precast thresholds are made a little longer than the common plinthblocks 23 (eg. 3' 9" as against 2 6"), and it is for this reason that a longer block 2a is incorporated to enable a balanced assembly to be made. The presence of the plinth quoin blocks enables a rectangular plinth base (one half of which is depicted in Figure 5) to be laid right around a building such as a pair of semi-detached houses. The individual plinth blocks including the thresholds are all rebated at their ends where indicated at 28 (Figures 69) so that when said blocks are laid end to end as shown in Figure 5 there are provided socket-like recesses 29 adapted to receive the feet of the upright columns. The specially shaped recess 30 formed in the relevant end of each plinth quoin block 24 is adapted, in con junction with the rebate 28 in the adjoining end of a common plinth block 23, to provide an aperture to receive the foot of a corner column 8. The actual forms of the plinth blocks and thresholds are clearly depicted in Figures 6-11. Suflice it to mention that the upper surface of the blocks '23, 24 and 26 are chamfered at 31 adjoining their outer edges. The front porch threshold 25 has a rounded nosing at 32 (see Figures 9 and 11) and is formed at its opposite ends, adjacent to and in front of the rebates 28, with flat-topped stools 33 (Figures 9 and-l0) of the same height as the adjoining common plinth blocks. The threshold 25, moreover, is strengthened by means of three A" diameter steel reinforcing bars 34 arranged as shown in Figure 11.

It will now be convenient to describe the precast upright columns which are set in the laid plinth course 3. Thus, the common columns 4 shown in Figures 12-l6 are each :7 0" or thereabouts in height and have a rectangular foot 38 4 /2" high and measuring 5%" at the front and 6%" at the side. From foot to head, this particular column is, with a possible exception later to be described, of the same cross-sectional shape comprising, from front to back and as shown more clearly in Figure 14, a frontal dovetail formation 39 about A thick having convergent vertical faces 39a-one at each side of the column-then a parallel-sided portion 40 approximately 2% thick followed by a rear dovetail formation 41 with diverging vertical faces 41a. The formation 41 is 3% thick and widens from 3" at its root to about 4 /2" at the back of the column. The common column is reinforced by two lengths 42 of 7 diameter mild steel rod which are spaced 3%" apart parallel to each other and extend right throughout the column. The upper end portions 42a of these two rods project above the head of the column to the extent of, say, 11". A common column of this form is adapted to mate with external cladding slabs 1113 'and internal panelling blocks 14-17 of 3" in thickness, with a cavity C of 2 /2" between them. Now in each of Figures 12 and 13, the common column 4 is shown as having a portion 43 about 11" long on which the dovetail formations 39 and 41 are omitted. That is to say, the said formations are interrupted or gapped at this location to permit of insertion of the cladding slabs and the internal panelling blocks and thereby facilitate their engagement with the column by a longitudinal sliding action. If desired, however, each common column may be made of the same cross-sectional shape from foot to head, in which instance and as previously mentioned, the various components may be so formed that the external slabs and the internal panelling blocks can be simply pushed straight into position without being caused first to slide along the columns. In this connection, and as will be apparent from Figures 4043, sharp vertically disposed corners of the dovetail formations on or in the slabs and the blocks may be removed. By the adoption of this expedient, the widest portion 44a of, say, the dovetail formation 44 on, for instance, a cladding slab 10 (Figure 40) is slightly reduced in width, whereas the Width of the narrowest portion 45a of a dovetail recess in a slab 11 is commensurately increased, as the case may be, thereby enabling the slab, when being laid, to be forced back into position beyond the widest portion of a complementary dovetail formation 39 on an upright column. When a slab is pushed back into position there are small spaces such as s (Figure 45a) between its oblique vertical edges or faces and the vertical mating faces of the adjoining column or columns, but since these spaces are filled with cement-mortar the components are effectively interlocked and tied together.

Most of the remaining forms of columns are based generally on the common column 4 described above, being similarly reinforced but modified to suit their purpose and position. Thus, a right or a left-handed window jamb column 5 like that illustrated in detail in Figures 17-23 is of generally the same basic cross-sectional shape as a common column 4 for a distance of about 21 5%" above its foot 38, then for a further window sills.

distance of 3" upwards this section is modified by making the appropriate side of the column entirely flat as indicated at 46 in Figures 18 and 21. The same side of the remaining upper portion of the column 5 has cast on the front thereof a forwardly projecting and attractively shaped window jamb or post 47 which is nosed or rounded at the front. The corresponding side of the rear portion of this window column 5 has formed therein a right angular rebate 48. The column has a plurality of wooden plugs 49 (Figure 18) cast therein at equal distances apart to facilitate the attachment thereto of a window frame of wood or metal.

A window mullion column 6 (see Figures 24-30) is again of the aforesaid basic cross-sectional shape from its foot 38 up to a point 3 below the mullion 50 at which location the section changes, as depicted in Figure 27, to plain rectangular to enable it to interengage on opposite sides, where indicated at 51, with precast The mullion 50 itself extends up to the head, and projects forwardly from the front of the column and is formed with two adjacently disposed rounded noses or ribs 50a. Wooden plugs 5012 are cast in at the back of the mullion.

A right or a left handed door column 7 (Figures 31-35) is of the same cross-sectional shape from the top of its foot 38 up to the head, one side being identical with a common column 4 and the other side being modified to present a solid door jamb 52 having a nosed front 52a and a flat side 5212 wherein are cast wooden plugs 53 to which the relevant side of a door frame can be secured.

A corner column 8 (Figures 36-39)-one of which is provided at each of the four corners of a rectangular building-has dovetail formations 54 and 55 of the same characteristic shape and dimensions as those on a common column 4 but whereas in the latter the formations 39 and 41 are provided on two parallel sides, in a corner column 8 the corresponding formations 54 and 55 are on two adjoining sides which are disposed at right angles and meet in a point 56. The remaining two sides 57 and 58 of a corner column 8 are flat but instead of meeting in a sharp corner the latter is omitted so as to provide an additional fiat vertical face 59, which adjoins and is obliquely disposed with respect to the other two. Each corner column is reinforced by three separate A diameter mild steel rods 42.

The precise forms of the various upright columns 48 will be readily apparent from the horizontal cross-sectional views of the same.

Referring again to the external cladding slabs some of these, like that illustrated at 10 in Figure 40, are rebated or Winged at their opposite ends as indicated at 75 so as to provide on their backs the aforementioned dovetail formations 44 having divergent obliquely disposed vertical end faces 44b. Other of the cladding slabs, such as that depicted at 11 in Figure 41, are plain-ended and have formed in their rear faces 11a, centrally between their ends, dovetail recesses 45 with convergent sides 45b. The slabs 12 (Figure 42) are each equivalent to half of one of the slabs 10, being winged at one end only and plain-ended at the opposite end. As will be clear from Figure 1, right and left-handed half slabs of'this character are laid with their notched ends adjoining a door opening 77 and a window opening 79. Opposite handed quoin slabs like that shown at 13 in Figure 43, are, of course, laid at the corners of the walling W and the recesses 85) formed in the relevant ends thereof are made to fit corner columns 8. All of the external cladding slabs are grooved right around their peripheries to receive cement mortar, the grooves of semi-circular shape in cross-section, being indicated by the reference numeral 81. The cladding slabs are laid in superimposed stretcher courses resembling Ashlar bonding which, generally speaking, means that the external cladding comprises alternate courses composed of double-winged slabs 10 each 6-. interfittedwith the dovetail formations 39 of two upright columns, and intervening courses of plain-ended slabs 11 and half slabs 12 (where appropriate) each interengaged with a single column. The cladding slabs may conveniently be precast in 1:2:4 concrete, i.e. one part of cement, two parts of sand and four parts of, say aggregate by volume. Cladding slabs, in selected positions, may incorporate air bricks as at 82 in Figure 1.

Since the internal panelling blocks are not bonded like the cladding slabs but are merely made to fill in the spaces between the upright columns as illustrated in Figure 3, then each of the blocks 14, 15, 16 and 17 is splayed at both ends so that, regarded in plan or in cross-section, the block itself is of dovetail form, and when these blocks are first laid and cemented in position to fill in the spaces between the columns and so provide the inner leaf or skin, the rear faces of the said columns will be initially exposed to viewflush with the inwardly facing surfaces of the blocks. The panelling blocks or fillers are preferably of clinker to provide thermal insulation and to present a rough surface for keying with wall plaster. To provide for continuity of the insulation at least the rear portion of each of the precast upright columns may be: composed of a layer 84 of foamed slag concrete. Like the:

external cladding slabs, the internal panelling blocks are: rectangular in shape and they are grooved at 85 to re-- ceive cement mortar. Some of the panelling blocks are: 3'4" long and only a few of these are required in a building. The majority of the panelling blocks are like those indicated at 15 and are, in this example, only 2'1 in length. A few of the panelling blocks required are splayed at one end only and are rebated at the opposite end. Air bricks may conveniently be provided in selected panelling blocks.

The system of erecting a building or like structure with Walls of the character described accordingly includes the initial steps of laying plinth blocks, including quoins and thresholds as aforesaid, above a damp-proof course of a supporting foundation, then erecting the precast upright columns on the plinth base with their feet 38 or 63 located in the socket-like recesses 29 produced, wedging the columns in position, and, before cladding and panelling commences, temporarily applying a template to the heads of the columns for the purpose of tying and bracing the same. At this stage, cement grout is poured around the bases of the columns. Then, after the grout has set, and the various external cladding slabs and the internal panelling blocks have been laid and cemented in position, together with the window cills 87, the course 18 of combined lintel and troughing blocks is laid along the tops of the walls W and the heads of the various upright columns. This course, in so far as it applies to one house of a pair of semi-detached houses, is shown in Figure 47. The said course 18 is composed of a plurality of straight common lintel-troughing blocks 90, linteltroughing blocks 91 and 92 similar to blocks 91) but with mouldings 93 and 94 thereon for disposal above window and door openings and right and left-handed quoin lintel blocks such as 95. A common linteltroughing block is illustrated in detail in Figures 48, 49 and 50; as will be seen, this block is deeply channelled from end to end so that it is actually in the form of a trough comprising a flat bottom 90a and two upright parallel side walls 90b and 900 which are somewhat thicker where they adjoin the bottom than they are at their upper edges. The block is, therefore, entirely open at its opposite ends and each end of the flat bottom 90a has formed therein a rectangular recess r one side of which is in the same plane as the inner face of the upright side wall 90c. The lintel-troughing block 90 is 25% long, 11%" high and 8 /2" wide: its flat bottom is 2%" thick, whereas the thickness of the lower portions of the side walls 90b and 900 is only 1 /2. Owing to the comparative thinness of these walls it is found desirable to incorporate into the inner faces of the troughing block an expanded metal cage which serves to reinforce the block and maintain its shape. After the said block has been cast, transverse mild steel bars 96, e.g. of in diameter, are fixed in position as shown in Figures 48, 49 and 50.

Each quoin lintel block 95 is 3' /z in length, and whilst at one end it is of the same form as a block 90 at the opposite end it is shaped as depicted in Figure 51. That is to say, the said opposite end is partly closed at 98 whilst the immediately adjoining portion of the upright side Wall 95a is gapped at 99 to receive the relevant recessed end of a common lintel-troughing block 90 disposed at right angles thereto. At a location adjacent to the gap 99 in the wall 95a, the bottom 95b of the quoin lintel block 95 has provided therein a recess r The transverse section of a quoin lintel block 95 is the same as that of a common lintel-troughing block 90.

When the various lintel-troughing blocks are laid end to end in the manner represented in the diagrammatic layout of Figure 47, the adjoining complementary recesses r or r and r as the case may be, produce in the bottom of the continuous troughing apertures 130 which are spaced apart to correspond with the spacing of the upright columns. The upper end portions 42a of the reinforcing rods of the precast columns 4, 5, 6, 7 and 8 extend vertically upwards through the relevant apertures 100 into the aligned troughs. This is clearly shown in Figure 2. In situ concrete 101 poured into the said troughs runs down into and fills the apertures 160 so as to produce a mechanical tie with the heads of the upright columns. The in situ concrete 101 in the troughs forms, around a pair of houses, a continuous or endless beam from which extend integral soffit portions constituting reinforced in situ extensions of the columns. That is to say, the in situ concrete filling the apertures 1160 connects the upper ends of the columns with the continuous beam and is itself reinforced by the upwardly directed extensions of the column reinforcement. Moreover, the continuous beam is also preferably reinforced by placing into the troughs, before concrete is poured thereinto, steel rods or bars such as 102 suitably grouped together and connected by embracing metal ties 103 (see Figure 2).

The apertures 109 formed in the lintel-troughing blocks extend vertically downwards from the bottoms of the troughs to the undersides of, the said blocks, and the sides of these apertures, or of the entrances thereto, are downwardly tapered to provide a lead-in for the in situ concrete. The sides of the lintel-troughing blocks which are to face inwardly may, at least in part, be composed of foamed slag aggregate: the reason for this is that these sides, when the lintel troughing blocks are laid and cemented in position upon the topmost cladding slabs and internal panelling blocks, lie flush with and, indeed, form the upper portion of the inner leaf.

Although the wall construction hereinbefore specifically described includes internal panelling blocks which are interengaged with dovetail formations on the upright columns, it is to be clearly understood that the invention includes within its scope a construction wherein the columns are interengaged with external cladding slabs only, in which instance the inner leaf of the wall may consist simply of boarding or the like such as 114 (Figure 4) applied to the fiat inner faces of the columns.

In either event, condensation collected within the cavity, i.e. in the space between the inner and outer leaves of the wall, is collected at the bottom of the said cavity and is deflected outwards through weep holes located immediately above the plinth course 3. In this connection there may be provided in the bottom of the cavity (see Figure 2) a cement fillet of triangular section having a sloping upper surface leading down to the weep holes. The said upper surface of the cement fillet may with advantage have a bituminous coating.

The invention includes not only a building or structure embodying the improved outer wall construction, but also 8 the system of building such a wall and individual coniponents required in its section.

All of the components may advantageously be cast face downwards.

As to the upright columns these may be cast in moulds of wood or steel. Each mould may be either designed to make one column at a time, or it may be divided longitudinally into a plurality of compartments and be thereby adapted to produce two or more columns simultaneously. Reinforcing rods and any other required column reinforcement are placed in the moulds prior to the concrete being poured or placed thereinto, and are held in jigs appropriately positioned within the form work. After or during the pouring or placing of the concrete in the moulds the latter are laid on tables which are adapted to be vibrated, e.g. by electrical impulse. If desired, colouring matter may be incorporated into the body of the concrete so that it will automatically appear on the. faces of the precast columns. After being removed from the moulds, and whilst still green, i.e. not finally set, the columns are faced with the aid of a wooden float. The finished columns are cured for a period of several days.

When columns are being mass produced, the apparatus employed may include conveyors whereby the moulds are moved from station to station in an orderly and progressive manner.

We claim:

1. A prefabricated wall, comprising, in combination. a base composed of a course of precast plinth blocks having reentrant portions in their respective top surfaces so as to form recesses spaced from each other horizontally at predetermined intervals; a plurality of precast upright columns of reinforced concrete. each of said columns being inserted with its lower end in one of said recesses whereby said columns are spaced at said intervals, said columns having reinforcing bars extending longitudinally thereof and projecting with a portion thereof beyond the top of the respective column, said columns further having a number of longitudinally extending faces of which at least one is an outside face and at least one other face is a lateral face having a first edge defined by the intersection of said lateral face with said outside face, and a second edge remote therefrom, said lateral face having an outwardly diverging dovetail portion adjacent to at least one of said edges; an outer leaf comprising at least one course of external cladding slabs each having an outer and an inner face and lateral end edges facing in the longitudinal direction of said course, the end edges of any one slab and of a neighboring slab, respectively, extending parallel with and adjacent to each other in the plane of said outer faces thereof and being aligned with each other, while said inner faces of said slabs are provided with reentrant dovetail recesses extending parallel with said lateral end edges and being spaced from each other, each of said slabs being respectively inserted between two of said columns and attached to said respective two columns by engagement, respectively, of said spaced reentrant dovetail recesses with said diverging dovetail portions of said two columns, respectively; and a wall top including a course of precast elongated lintel units having an upwardly open channel portion and a flat bottom portion with recesses therein forming openings spaced from each other at said predetermined intervals, said lintel units being placed with said flat bottom portions on top of said columns with said projecting portions of said reinforcing bars thereof extending through said openings, and with their respective ends abutting against each other in longitudinal direction, said lintel units being permanently connected with said columns by concrete filled in situ into said channel portions and into said openings.

2. A prefabricated wall, comprising, in combination, a base composed of a course of precast plinth blocks having reentrant portions in their respective top surfaces so as to form recesses spaced from each other horizon:

tally at predetermined intervals; a plurality of precast upright columns of reinforced concrete, each of said columns being inserted with its lower end in one of said recesses whereby said columns are spaced at said intervals, said columns having reinforcing bars extending longitudinally thereof and projecting with a portion thereof beyond the top of the respective column, said columns further having a number of longitudinally extending faces of which at least one is an outside face and at least one other face is a lateral face having a first edge defined by the intersection of said lateral face with said outside face, and a second edge remote therefrom, said lateral face having an outwardly diverging dovetail portion adjacent to at least one of said edges; an outer leaf comprising at least one course of external cladding slabs each having an outer and an inner face and lateral end edges facing in the longitudinal direction of said course, the end edges of any one slab and of a neighboring slab, respectively, extending parallel with and closely adjacent to each other in the plane of said outer faces thereof and being aligned with each other, while said inner faces of said slabs are provided with reentrant dovetail recesses extending parallel with said lateral end edges and being spaced from each other, each of said slabs being respectively inserted between two of said columns and attached to said respective two columns by engagement, respectively, of said spaced reentrant dovetail recesses with said diverging dovetail portions of said two columns, respectively; and a wall top including a course of precast elongated lintel units having an upwardly open channel portion and a flat bottom portion with recesses therein forming openings spaced from each other at said predetermined intervals, said lintel units being placed with said flat bottom portions on top of said columns with said projecting portions of said reinforcing bars thereof extending through said openings, and with their respective ends abutting against each other in longitudinal direction, said lintel units being permanently connected with said columns and a plurality of said lintel units being connected with each other by concrete filled in situ into said channel portions of said lintel units and into said openings.

3. A prefabricated wall, comprising, in combination, a base composed of a course of precast plinth blocks having reentrant portions in their respective top surfaces so as to form recesses spaced from each other horizontally at predetermined intervals; a plurality of precast upright columns of reinforced concrete, each of said columns being inserted with its lower end in one of said recesses whereby said columns are spaced at said intervals, said columns having reinforcing bars extending longitudinally thereof and projecting with a portion thereof beyond the top of the respective column, said columns further having a number of longitudinally extending faces of which at least one is an outside face and at least one other face is a lateral face having a first edge defined by the intersection of said lateral face with said outside face, and a second edge remote therefrom, said lateral face having an outwardly diverging dovetail portion adjacent to at least one of said edges; an outer leaf comprising at least one course of external cladding slabs each having an outer and an inner face and lateral end edges facing in the longitudinal direction of said course, the end edges of any one slab and of a neighboring slab, respectively, extending parallel with and closely adjacent to each other in the plane of said outer faces thereof and being aligned with each other, while said inner faces of said slabs are provided with reentrant dovetail recesses extending parallel with said lateral end edges and being spaced from each other, each of said slabs being respectively inserted between two of said columns and attached to said respective two columns by engagement, respectively, of said spaced reentrant dovetail recesses with said diverging dovetail portions of said two columns, respectively; an inner leaf comprising a plurality of fiat wall panels attached t6 those faces of said columns which are opposite to said outer faces thereof so as to be spaced from said outer leaf by an interval; and a wall top including a course of precast elongated lintel units having an upwardly open channel portion and a flat bottom portion with recesses therein forming openings spaced from each other at said predetermined intervals, said lintel units being placed with said flat bottom portions on top of said columns with said projecting portions of said reinforcing bars thereof extending through said openings, and with their respective ends abutting against each other in longitudinal direction, said lintel units being permanently connected with said columns by concrete filled in situ into said channel portions and into said openings.

4. A prefabricated wall, comprising, in combination, a base composed of a course of precast plinth blocks having reentrant portions in their respective top surfaces so as to form recesses spaced from each other horizontally at predetermined intervals; a plurality of precast upright columns of reinforced concrete, each of said columns being inserted with its lower end in one of said recesses whereby said columns are spaced at said intervals, said columns having reinforcing bars extending longitudinally thereof and projecting with a portion thereof beyond the top of the respective column, said columns further having a number of longitudinally extending faces of which at least one is an outside face and at least one other face is a lateral face having a first edge defined by the intersection of said lateral face with said outside face, and a second edge remote therefrom, said lateral face having an outwardly diverging dovetail portion adjacent to at least one of said edges; an outer leaf comprisingat least one course of external cladding slabs eachhaving an outer and an inner face and lateral end edges facing in the longitudinal direction of said course, the end edges of any one slab and of a neighboring slab, respectively, extending parallel with and closely adjacent to each other in the plane of said outer faces thereof and being aligned with each other, while said inner faces of said slabs are provided with reentrant 'clovetail recesses extending parallel with said lateral end edges and being spaced from each other, each of said slabs being respectively inserted between two of said columns and attached to said respective two columns by engagement, respectively, of said spaced reentrant dovetail recesses with said diverging dovetail portions of said two columns, respectively; an inner leaf comprising a plurality of flat wall panels attached to those faces of said columns which are opposite to said outer faces thereof so as to be spaced from said outer leaf by an interval; and a wall top including a course of precast elongated lintel units having an upwardly open channel portion and a flat bottom por tion with recesses therein forming openings spaced from each other at said predetermined intervals, said lintel units being placed with said flat bottom portions on top of said columns with said projecting portions of said reinforcing bars thereof extending through said openings, and with their respective ends abutting against each other in longitudinal direction, said lintel units being permanently connected with said columns and a plurality of said lintel units being connected with each other by concrete filled in situ into said channel portions of said lintel units and into said openings.

5. A prefabricated wall, comprising, in combination, a base composed of a course of precast plinth blocks having reentrant portions in their respective top surfaces so as to form recesses spaced from each other horizontally at predetermined intervals; a plurality of precast upright columns of reinforced concrete, each of said columns being inserted with its lower end in one of said recesses whereby said columns are spaced at said intervals, said columns having reinforcing bars extending longitudinally thereof and projecting with a portion thereof beyond the top of the respective column, said columns further having a number of longitudinally extending faces of which at least one is an outside face and at least one other face is a lateral face having a first edge defined by the intersection of said lateral face with said outside face, and a second edge remote therefrom, said lateral face having one outwardly diverging dovetail portion adjacent to each one of said edges; an outer leaf comprising at least one course of external cladding slabs each having an outer and an inner face and lateral end edges facing in the longitudinal direction of said course, the end edges of any one slab and of a neighboring slab, respectively, extending parallel with and closely adjacent to each other in the plane of said outer faces thereof and being aligned with each other, while said inner faces of said slabs are provided with reentrant dovetail recesses extending parallel with said lateral end edges and being spaced from each other, each of said slabs being respectively inserted between two of said columns and attached to said respective two columns by engagement, respectively, of said spaced reentrant dovetail recesses with said diverging dovetail portions of said two columns, respectively; an inner leaf comprising at least one course of paneling blocks having splayed lateral ends by means of which said paneling blocks are fitted between neighboring columns through engagement of said splayed ends with said outwardly diverging dovetail portions of the particular columns; and a wall top including a course of precast elongated lintel units having an upwardly open channel portion and a fiat bottom portion with recesses therein forming openings spaced from each other at said predetermined intervals, said lintel units being placed with said flat bottom portions on top of said columns with said projecting portions of said reinforcing bars thereof extending through said openings, and with their respective ends abutting against each other in longitudinal direction, said lintel units being permanently connected with said columns by concrete filled in situ into said channel portions and into said openings.

6. A prefabricated wall, comprising, in combination, a base composed of a course of precast plinth blocks having reentrant portions in their respective top surfaces so as to form recesses spaced from each other horizontally at predetermined intervals; a plurality of precast upright columns of reinforced concrete, each of said columns being inserted with its lower end in one of said recesses whereby said columns are spaced at said intervals, said columns having reinforcing bars extending longitudinally thereof and projecting with a portion thereof beyond the top of the respective column, said columns further having a number of longitudinally extending faces of which at least one is an outside face and at least one other face is a lateral face having a first edge defined by the intersection of said lateral face with said outside face, and a second edge remote therefrom, said lateral face having one outwardly diverging dovetail portion adjacent to each one of said edges; an outer leaf comprising at least one course of external cladding slabs each having an outer and an inner face and lateral end edges facing in the longitudinal direction of said course, the end edges of any one slab and of a neighboring slab, respectively, extending parallel with and closely adjacent to each other in the plane of said outer faces thereof and being aligned with each other, while said inner faces of said slabs are provided with reentrant dovetail recesses extending parallel with said lateral end edges and being spaced from each other, each of said slabs being respectively inserted between two of said columns and attached to said respective two columns by engagement, respectively, of said spaced reentrant dovetail recesses with said diverging dovetail portions of said two columns, respectively; an inner leaf comprising at least one course of paneling blocks having splayed lateral ends by means of which said paneling blocks are fitted between neighboring columns through engagement of said splayed ends with said outwardly diverging dovetail portions of the particular columns; and a wall top including a course of precast elongated lintel units having an upwardly open channel portion and a flat bottom portion with recesses therein forming openings spaced from each other at said predetermined intervals, said lintel units being placed with said flat bottom portions on top of said columns with said projecting portions of said reinforcing bars thereof extending through said openings, and with their respective ends abutting against each other in longitudinal direction, said lintel units being permanently connected with said columns and a plurality of said lintel units being connected with each other by concrete filled in situ into said channel portions of said lintel units and into said openings.

References Cited in the file of this patent UNITED STATES PATENTS 1,072,230 Howard Sept. 2, 1913 1,794,079 Kellett Feb. 24, 1931 1,804,320 Cross May 5, 1931 2,078,069 Eliel Apr. 20, 1937 2,320,690 Willis June 1, 1943 2,352,338 Muirhead June 27, 1944 2,547,347 Stoldt Apr. 3, 1951 FOREIGN PATENTS 417,763 Italy of 1947 583,535 France of 1924 

